/*
 * Copyright (c) "Neo4j"
 * Neo4j Sweden AB [http://neo4j.com]
 *
 * This file is part of Neo4j.
 *
 * Neo4j is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.neo4j.kernel.impl.transaction.state.storeview;

import static java.util.stream.StreamSupport.stream;
import static org.apache.commons.lang3.RandomStringUtils.randomAscii;
import static org.junit.jupiter.api.Assertions.assertTrue;
import static org.neo4j.io.pagecache.context.EmptyVersionContextSupplier.EMPTY;
import static org.neo4j.memory.EmptyMemoryTracker.INSTANCE;
import static org.neo4j.test.PageCacheTracerAssertions.assertThatTracing;
import static org.neo4j.test.PageCacheTracerAssertions.pins;

import org.junit.jupiter.api.Test;
import org.neo4j.common.EntityType;
import org.neo4j.configuration.Config;
import org.neo4j.graphdb.Label;
import org.neo4j.graphdb.Transaction;
import org.neo4j.internal.schema.IndexDescriptor;
import org.neo4j.io.pagecache.context.CursorContextFactory;
import org.neo4j.io.pagecache.tracing.DefaultPageCacheTracer;
import org.neo4j.kernel.impl.api.index.IndexProxy;
import org.neo4j.kernel.impl.api.index.IndexingService;
import org.neo4j.kernel.impl.api.index.StoreScan;
import org.neo4j.kernel.impl.coreapi.InternalTransaction;
import org.neo4j.kernel.impl.coreapi.schema.IndexDefinitionImpl;
import org.neo4j.kernel.internal.GraphDatabaseAPI;
import org.neo4j.lock.LockService;
import org.neo4j.scheduler.JobScheduler;
import org.neo4j.storageengine.api.StorageEngine;
import org.neo4j.test.extension.DbmsExtension;
import org.neo4j.test.extension.Inject;

@DbmsExtension
class LabelScanNodeViewTracingIT {
    @Inject
    private GraphDatabaseAPI database;

    @Inject
    private StorageEngine storageEngine;

    @Inject
    private LockService lockService;

    @Inject
    private JobScheduler jobScheduler;

    @Inject
    private IndexingService indexingService;

    @Test
    void tracePageCacheAccess() throws Exception {
        int nodeCount = 1000;
        var label = Label.label("marker");
        try (var tx = database.beginTx()) {
            for (int i = 0; i < nodeCount; i++) {
                var node = tx.createNode(label);
                node.setProperty("a", randomAscii(10));
            }
            tx.commit();
        }

        var labelId = getLabelId(label);

        var cacheTracer = new DefaultPageCacheTracer();
        CursorContextFactory contextFactory = new CursorContextFactory(cacheTracer, EMPTY);
        IndexProxy indexProxy = indexingService.getIndexProxy(findTokenIndex());

        var scan = new LabelIndexedNodeStoreScan(
                Config.defaults(),
                storageEngine.newReader(),
                storageEngine::createStorageCursors,
                lockService,
                indexProxy.newTokenReader(),
                new TestTokenScanConsumer(),
                null,
                new int[] {labelId},
                any -> false,
                false,
                jobScheduler,
                contextFactory,
                INSTANCE);
        scan.run(StoreScan.NO_EXTERNAL_UPDATES);

        assertThatTracing(database)
                .record(pins(102).noFaults())
                .block(pins(113).noFaults())
                .matches(cacheTracer);
    }

    private int getLabelId(Label label) {
        try (var tx = database.beginTx()) {
            return ((InternalTransaction) tx).kernelTransaction().tokenRead().nodeLabel(label.name());
        }
    }

    private IndexDescriptor findTokenIndex() {
        try (Transaction tx = database.beginTx()) {
            var nodeIndex = stream(tx.schema().getIndexes().spliterator(), false)
                    .map(indexDef -> ((IndexDefinitionImpl) indexDef).getIndexReference())
                    .filter(index -> index.isTokenIndex() && index.schema().entityType() == EntityType.NODE)
                    .findFirst();
            assertTrue(nodeIndex.isPresent());
            return nodeIndex.get();
        }
    }
}
